I'm trying to include some graphics into my report, and I can't find the normal width which can take an image to respect the margin-left and the margin-right of a page.
Here is the code that I've tried :
\begin{figure}[H]
\hfill{}\includegraphics[scale=0.8]{images/seq_auth}\hfill{}
\caption{abc}
\label{fg:seq_auth}
\end{figure}
But, the font of the text that is part of the graphic is too small to see when I've printed it. So, I thought that I maybe need to make it as wide as possible.
Any suggestions, please ?

\includegraphics[width=\linewidth]{images/seq_auth}only. Remove both\hfill{}and use\centeringinside thefigureenvironment. – Sigur Jan 24 '14 at 18:08